Dihydrogen reacts with CO at 700 K in the presence of a catalyst `ZnO""//Cr_2 O_3` to form formaldehyde.

Explanation

To determine whether the statement "Dihydrogen reacts with CO at 700 K in the presence of a catalyst ZnO/Cr2O3 to form formaldehyde" is true or false, we can analyze the reaction step by step.

### Step-by-Step Solution:

1. **Understanding the Reactants and Conditions**:
- The reactants in this scenario are dihydrogen (H2) and carbon monoxide (CO).
- The reaction occurs at a temperature of 700 K.
- A catalyst composed of zinc oxide (ZnO) and chromium(III) oxide (Cr2O3) is used.
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